The interaction of dietary calcium with dietary cadmium is being investigated at the intestinal level. The in vitro synthesis of cadmium binding protein (metallothionein) is being investigated. BIBLIOGRAPHIC REFERENCE: Cousins, R.J., R.A. Wynveen, K.S. Squibb and M.P. Richards. Double Label Counting of Metal Nuclides with H3 or C14 by Liquid Scintillation Counting. Anal. Biochem. 65:412-417 (1975).